Heat-conducting tube



Sept. 30, 1930.

J. B. MURRAY ET AL HEAT CONDUCTING TUBE Filed June 18, 1924 INVENTORS Patented Sept, 30, 1930 UNITED STATES PATENT OFFICE JOSEPH B. MURRAY AND THOMAS E. MURRAY, JR., BROOKLYN, NEW YORK, ASSIGN- ORS TO METROPOLITAN ENGINEERING COMPANY, A CORPORATION OF NEW YORK HEAT-CONDUCTING TUBE I Application filed June 18,

In certain prior applications, Nos. (542,427 filed May 31st, 1923, and 642,725 filed June 1st, 1923, which has since matured into Patent No. 1,746,711 dated Feb. 11, 1930, there is described a certain hollow construction for walls and other parts of boilers or heaters and made up of tubes of rectangular, circular or irregular cross-section with fins or flanges extending lengthwise thereof so as to provide a heating surface exposed to the heating gases greater than the surface which is in contact with the water or otherfluid in the tube.

The present invention provides a unit and a method of producing the same from which such boiler Walls and the like may be built.

' The accompanying drawings illustrate embodiments ofthe invention.

Fig. 1 is a horizontal section of a side wall of a boiler built with the tubular units of the invention;

Figs. 2 to 8 are plans of various forms of unit made in accordance with this invention.

In a co-pending application, Serial No. 715,369, filed May 23rd, 1924, we have described a unit for the purpose stated made of tubes with longitudinal flanges abutting at their edges against the tube and buttwelded thereto. The units of the present application are made with fins or flanges of metal which extend continuously through to the inside of the tube so as to ensure a perfect path for conduction of heat to the water in the tubes.

An example-of a boiler Wall built up of these units is shown in Fig. 1. Each unit comprises a tube 1 with flanges extending from opposite sides and overlapping to form a screen within the wall proper; which is 'made up of tire-bricks 3 on the outside of which are tiles 4 of non-conducting material and finally a shell 5 of sheet steel. The tins or flanges may be made of various standard rolled shapes, many of which are well adapted for thepurpose. According to Fig. 2,

a T-shape 6 is arranged with its head 7 within the tube and the edges of the tube coming together at the base of the head and welded; either by butt-welding,- or by arc-welding metal 8, or by both methods. A flange 1924. Serial No. 720,736.

of the same sort may be repeated at the opposite side of the tube, the latter in that case being formed of two segments. And a similar flange or flanges may be applied at other points wherever it is desired to extend the conducting surface. The same is true of the other constructions indicated in detail, only a single flange being shown for the sake of simplicity.

In Fig. 3, the flange is composed of a so heavy bar 9 which is rolled with grooves 10 J at its opposite faces near one end, and the edges of the tube are welded in these grooves.

According to Fig. 4, a rolled shape 11 of dumb-bell cross-section is used with the. edges of the tube coming against the narrow portion of the shape and welded by means of arc-deposited metal 8.

According to Fig. 5, a shape 12 is used h with a bulb 13 on the outer edge and a rounded head 14 on the inner edge; the edges of the tube being brought against the reduced web of the shape and welded as before. An enlargement on the outer edge as shown in Fig. 5 and to a certain extent in Fig. 4 is advantageous in that this is the part which is farthest from the cooling client of the water and: is most liable to rapid burning away.

According to Fig. 6. a one-sided shape 15 is used with an end flange 16 within the tube and an intermediate. flange 17 on the outside. the edges of the tube 1 being located against the part of the shape between these two flanges and being fastened by welding metal 8.

According to Fig. 7, a shape 18 is used which is practically a symmetrical development of that-of Fig. 6, with double flanges 19 and 20 between which the edges of the tube 1 are located and fastened by welding metal 8.

While it is advantageous to have an enlargement of the shape on the inside of the tube forbetter locking of the two together, this is not essential.

In Fig. 8. we have shown a plain flat bar 21 with its edge extending to the inner face of the tube (and it may be extended more or less into the tube) and fastened to the edges extension of the fin into the tube as herein" of the tube by arc-welding metal 8 or by buttwelding to the. edges of the tube, or by both means.

lVith the constructions shown, as the conduction of heat to the water is better, so the cooling effect of the water 011 the fins is also greater and their life under the oxidizing effect of'the flame will be greater. While, therefore, itis preferred to make these flanges of metal better adapted to resist oxidation than the ordinary steel of the tube, or to coat them with a resistantcoating, such precautions are not so important as vwhere the fins do not extend to the insides of the tubes.

In the previous schemes for producing tubes of this sort of wrought metal, that is of rolled strips or shapes combined with tubes drawn -orbent-up from sheets, the fin has generally been applied only to the outside of the tube with a jointwhich would be less effective in conducting heat than the integral described. I

Though we have described with great par ticularity of detail certain embodiments of our invention, yet it is not to be understood therefrom that the invention is restricted to the particular embodiments disclosed. Various modifications thereof in detail and in the arrangement of the parts may be made by those skilled in the art without departing from the invention as defined in the following claims.

What we claim is 2-- 1. A heat conducting unit comprising a tubular member with a solid longitudinal flange consisting of a steel shape rolled separately from the tube. said shape having a thin external portion and an integral portion extending to the inside of the tube with a thickened enlargement on its inner edge bearing against the inner side of the tube, the edges of the tubular-portion being welded to the faces of the rolled shape.

2. The combination of a plurality of water tubes for boilers comprising tubular members spaced apart with longitudinal flange members in the intermediate spaces, the flange members being separately formed and the tubular members having edges welded to the faces of the flange members, the

flange members forming thin external .fins

' of less width than the diameter of the tubular members with an extended area exposed to the heat and having free inner edges throughout their length exposed to the water within conducting heat directly to the the tubes.

3. A heat conducting unit comprising a tubular member with a longitudinal flange formed separately from and welded to the tubular portion, having a comparatively thin water within portion adjacent to the tube and having a the tubular members so that the flange members provide a continuous integral path for 

